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//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions
// are met:
// * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
// * Redistributions in binary form must reproduce the above copyright
// notice, this list of conditions and the following disclaimer in the
// documentation and/or other materials provided with the distribution.
// * Neither the name of NVIDIA CORPORATION nor the names of its
// contributors may be used to endorse or promote products derived
// from this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS ``AS IS'' AND ANY
// EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
// PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
// CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
// EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
// PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
// PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
// OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
//
// Copyright (c) 2008-2018 NVIDIA Corporation. All rights reserved.
// Copyright (c) 2004-2008 AGEIA Technologies, Inc. All rights reserved.
// Copyright (c) 2001-2004 NovodeX AG. All rights reserved.
// ****************************************************************************
// This snippet illustrates simple use of the PxSpatialIndex data structure
//
// Note that spatial index has been marked as deprecated and will be removed
// in future releases
//
// We create a number of spheres, and raycast against them in a random direction
// from the origin. When a raycast hits a sphere, we teleport it to a random
// location
// ****************************************************************************
#include <ctype.h>
#include "PxPhysicsAPI.h"
#include "../SnippetCommon/SnippetPrint.h"
#include "../SnippetUtils/SnippetUtils.h"
using namespace physx;
PxDefaultAllocator gAllocator;
PxDefaultErrorCallback gErrorCallback;
PxFoundation* gFoundation = NULL;
static const PxU32 SPHERE_COUNT = 500;
float rand01()
{
return float(rand())/RAND_MAX;
}
struct Sphere : public PxSpatialIndexItem
{
Sphere()
{
radius = 1;
resetPosition();
}
Sphere(PxReal r)
: radius(r)
{
resetPosition();
}
void resetPosition()
{
do
{
position = PxVec3(rand01()-0.5f, rand01()-0.5f, rand01()-0.5f)*(5+rand01()*5);
}
while (position.normalize()==0.0f);
}
PxBounds3 getBounds()
{
// Geometry queries err on the side of reporting positive results in the face of floating point inaccuracies.
// To ensure that a geometry query only reports true when the bounding boxes in the BVH overlap, use
// getWorldBounds, which has a third parameter that scales the bounds slightly (default is scaling by 1.01f)
return PxGeometryQuery::getWorldBounds(PxSphereGeometry(radius), PxTransform(position));
}
PxVec3 position;
PxReal radius;
PxSpatialIndexItemId id;
};
Sphere gSpheres[SPHERE_COUNT];
PxSpatialIndex* gBvh;
void init()
{
gFoundation = PxCreateFoundation(PX_FOUNDATION_VERSION, gAllocator, gErrorCallback);
gBvh = PxCreateSpatialIndex();
// insert the spheres into the BVH, recording the ID so we can later update them
for(PxU32 i=0;i<SPHERE_COUNT;i++)
gSpheres[i].id = gBvh->insert(gSpheres[i], gSpheres[i].getBounds());
// force a full rebuild of the BVH
gBvh->rebuildFull();
// hint that should rebuild over the course of approximately 20 rebuildStep() calls
gBvh->setIncrementalRebuildRate(20);
}
struct HitCallback : public PxSpatialLocationCallback
{
HitCallback(const PxVec3 p, const PxVec3& d): position(p), direction(d), closest(FLT_MAX), hitSphere(NULL) {}
PxAgain onHit(PxSpatialIndexItem& item, PxReal distance, PxReal& shrunkDistance)
{
PX_UNUSED(distance);
Sphere& s = static_cast<Sphere&>(item);
PxRaycastHit hitData;
// the ray hit the sphere's AABB, now we do a ray-sphere intersection test to find out if the ray hit the sphere
PxU32 hit = PxGeometryQuery::raycast(position, direction,
PxSphereGeometry(s.radius), PxTransform(s.position),
1e6, PxHitFlag::eDEFAULT,
1, &hitData);
// if the raycast hit and it's closer than what we had before, shrink the maximum length of the raycast
if(hit && hitData.distance < closest)
{
closest = hitData.distance;
hitSphere = &s;
shrunkDistance = hitData.distance;
}
// and continue the query
return true;
}
PxVec3 position, direction;
PxReal closest;
Sphere* hitSphere;
};
void step()
{
for(PxU32 hits=0; hits<10;)
{
// raycast in a random direction from the origin, and teleport the closest sphere we find
PxVec3 dir = PxVec3(rand01()-0.5f, rand01()-0.5f, rand01()-0.5f).getNormalized();
HitCallback callback(PxVec3(0), dir);
gBvh->raycast(PxVec3(0), dir, FLT_MAX, callback);
Sphere* hit = callback.hitSphere;
if(hit)
{
hit->resetPosition();
gBvh->update(hit->id, hit->getBounds());
hits++;
}
}
// run an incremental rebuild step in the background
gBvh->rebuildStep();
}
void cleanup()
{
gBvh->release();
gFoundation->release();
printf("SnippetSpatialIndex done.\n");
}
int snippetMain(int, const char*const*)
{
static const PxU32 frameCount = 100;
init();
for(PxU32 i=0; i<frameCount; i++)
step();
cleanup();
return 0;
}
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